Why Jogging Was So Dangerous In The 70s

By the end of the 1970s, jogging was becoming a regular hobby for many people. Capitalising on its rising popularity, the writer Jim Fixx released a guide titled ‘The Complete Book of Running.’ Fixx discussed the physical benefits of jogging, as well as focusing on the mental positives the sport can provide. From runners' high to higher self-esteem, Fixx claimed that jogging was more than just a fun thing to do. The runner became a mild-celebrity throughout the latter half of the '70s and featured in several television spots, including the puntastic commercial for American Express. Jim Fixx also went on to release several more books on his beloved activity.

During a daily run in 1984, however, Fixx began to feel peculiar. He stopped his run and suffered a heart attack on the side of the road. He was 52 years old. While a genetic predisposition is seen as the main culprit for his fatal cardiac arrest, jogging also played a part.

During aerobic exercise, muscles contract to help pump blood back to the heart. This lightens the load of pumping the heart has to carry out during exercise. However, as Jim just stopped his muscles stopped and the heart was pressured to pump more and more. A blockage in his arteries put further pressure on his ticker and caused it to arrest. Had Fixx reduced to a walk, he may have survived the episode. Never underestimate the importance of the cool down.